Note: In notes to Convergent Series publication, Niven says the story (as well as Bordered in Black) "does not belong to the Known Space universe. When I wrote [them] Known Space had not taken form. I was playing with some preliminary ideas [...] Hair styles and human colony worlds from this story later entered Known Space; but the story does not belong to that universe."

Synopsis: Accident sends a hyperspace ship billions of years into future, where Earth has lost its atmosphere and become tidal-locked. They land and use the drive to re-spin the Earth, which will melt frozen air preserved at the night side.